title: [The importance of N-acetylneuraminic acid and of its interaction with Ca++ in the stability of the erythrocytic membrane].
abstract: The aim of this paper is to draw information about influence of human red cell N-acetyl-neuraminic acid and its interaction with Ca++ on membrane itself stability. Then, changes of red cell behavior in reply to osmotic stress with and without Ca++ after treatment with neuraminidase has been studied. We noted that the treatment with neuraminidase causes spontaneous hemolysis (about 9%), independently of medium osmolarity. As regards membrane resistance to osmotic stretching, N-acetyl-neuraminic acid has a destabilizing effect on most erythrocytes whereas its interaction with Ca++ don't influences significantly membrane resistance to osmotic stretching. Nevertheless, in extreme conditions of osmolarity (i.e. when hemolysis of younger red cells occurs), destabilizing effect of N-acetyl-neuraminic acid is no longer observable and, on the contrary, when it interacts with Ca++, it increases the osmotic resistance of red cells.
mesh_terms: D002118:Calcium / Q000097:blood*; D004492:Edetic Acid / Q000494:pharmacology; D004910:Erythrocyte Membrane / Q000502:physiology*; D004912:Erythrocytes / Q000187:drug effects / Q000502:physiology*; D006461:Hemolysis; D006801:Humans; D066298:In Vitro Techniques; D009439:Neuraminidase / Q000494:pharmacology; D012794:Sialic Acids / Q000097:blood*; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D012794:Sialic Acids; D012965:Sodium Chloride; D004492:Edetic Acid; D009439:Neuraminidase; D002118:Calcium
vernacular_title: L'importanza dell'acico N-acetil-neuraminico e della sua interazione con Ca++ nella stabilita' della membrana eritrocitaria.